Relationship of urinary endothelin-1 with estimated glomerular filtration rate in autosomal dominant polycystic kidney disease: a pilot cross-sectional analysis.

BACKGROUND: The pathogenesis of progressive renal insufficiency in autosomal dominant polycystic kidney disease (ADPKD) is unclear. Evidence from experimental models of ADPKD suggests that elevated endothelin-1 (ET-1) drives cyst growth, renal fibrosis and loss of renal function, but whether ET-1 is elevated in humans with ADPKD is uncertain. METHODS: In a cross-sectional study of ADPKD we measured urinary ET-1, a surrogate for ET-1 in kidney cortex, in spot collections corrected for creatinine. The volume of each kidney was measured using MRI-based stereology. The relationship of urine ET-1 with MDRD eGFR and kidney volume was modeled by multiple linear regression with adjustment for clinical covariates. RESULTS: Patients with ADPKD were ages 18 to 53 with eGFRs (median, interquartile range) of 63.2 (43.5-80.2) ml/min/1.73 m(2) and albumin/creatinine ratios (ACR) of 115.0 (7.5-58.5) µg/mg. Urine ET-1 was inversely associated with eGFR (r = -0.480, P < 0.05) and positively (r = 0.407, P = 0.066) with ACR independent of age and female sex (P < 0.01). ET-1 appeared to be positively associated with total kidney volume (r = 0.426, P = 0.100), with a test for trend across urine ET-1 quartiles yielding z = 1.83, P = 0.068. ET-1 strongly correlated with NAGase (r = 0. 687, P = 0.001), a marker of tubular damage and a surrogate marker of renal disease progression in ADPKD. Of note, ET-1 levels in urine were not correlated with hypertension. CONCLUSIONS: In a translational study of patients with ADPKD, urinary ET-1 was inversely associated with eGFR and positively correlated with total kidney volume. Taken together with results from experimental models, these findings suggest that the role of ET-1 in ADPKD warrants further investigation.

Autopsy series of 68 cases dying before and during the 1918 influenza pandemic peak.

The 1918 to 1919 "Spanish" influenza pandemic virus killed up to 50 million people. We report here clinical, pathological, bacteriological, and virological findings in 68 fatal American influenza/pneumonia military patients dying between May and October of 1918, a period that includes ~4 mo before the 1918 pandemic was recognized, and 2 mo (September-October 1918) during which it appeared and peaked. The lung tissues of 37 of these cases were positive for influenza viral antigens or viral RNA, including four from the prepandemic period (May-August). The prepandemic and pandemic peak cases were indistinguishable clinically and pathologically. All 68 cases had histological evidence of bacterial pneumonia, and 94% showed abundant bacteria on Gram stain. Sequence analysis of the viral hemagglutinin receptor-binding domain performed on RNA from 13 cases suggested a trend from a more "avian-like" viral receptor specificity with G222 in prepandemic cases to a more "human-like" specificity associated with D222 in pandemic peak cases. Viral antigen distribution in the respiratory tree, however, was not apparently different between prepandemic and pandemic peak cases, or between infections with viruses bearing different receptor-binding polymorphisms. The 1918 pandemic virus was circulating for at least 4 mo in the United States before it was recognized epidemiologically in September 1918. The causes of the unusually high mortality in the 1918 pandemic were not explained by the pathological and virological parameters examined. These findings have important implications for understanding the origins and evolution of pandemic influenza viruses.

Protein changes in immunodepleted cerebrospinal fluid from a transgenic mouse model of Alexander disease detected using mass spectrometry.

Cerebrospinal fluid (CSF) is a low protein content biological fluid with a dynamic range spanning at least 9 orders of magnitude in protein content and is in direct contact with the brain. A modified IgY-14 immunodepletion treatment was performed to enhance analysis of the low volumes of CSF that are obtainable from mice. As a model system in which to test this approach, we utilized transgenic mice that overexpress the intermediate filament glial fibrillary acidic protein (GFAP). These mice are models for Alexander disease (AxD), a severe leukodystrophy in humans. From the CSF of control and transgenic mice we report the identification of 289 proteins, with relative quantification of 103 proteins. Biological and technical triplicates were performed to address animal variability as well as reproducibility in mass spectrometric analysis. Relative quantitation was performed using distributive normalized spectral abundance factor (dNSAF) spectral counting analysis. A panel of biomarker proteins with significant changes in the CSF of GFAP transgenic mice has been identified with validation from enzyme-linked immunosorbent assay (ELISA) and microarray data, demonstrating the utility of our methodology and providing interesting targets for future investigations on the molecular and pathological aspects of AxD.

Impact of Stress on the Immunogenic Potential of Adalimumab.

Monoclonal antibodies against tumor necrosis factor-alpha (TNFα) are widely used for treatment of inflammatory diseases. However, despite the inhibitory effect this class of drugs has on the immune system, anti-drug antibodies are often formed with continuous use. Particles formed during stress conditions, which can be used to simulate storage and handling conditions of commercial antibodies, have previously been associated with the formation of anti-drug antibodies. This study investigates the relationship between particles, oligomerization, folding and chemical degradation on the in vitro cytokine response toward the TNFα inhibitor adalimumab. Adalimumab aggregates generated using stir and heat stress were fractionated into distinct sub-populations, and their structure and immunogenic potential were evaluated. A chemically degraded sample of adalimumab was included to compare particle composition with the milder accelerated heat and stir stressed conditions. Particles from stressed adalimumab samples induced elevated cytokine levels and CD4+ T cell proliferation in vitro compared to non-stressed samples. Samples enriched with both submicron and subvisible particles of adalimumab induced the strongest cytokine release and the strongest CD4+ T cell proliferation despite maintaining some TNFα inhibitory functionality. Samples that were stressed and subsequently purified of subvisible and submicron particles did not elicit a significantly higher cytokine response or show increased CD4+ T cell proliferation compared to a non-stressed sample. Oxidation-induced chemical modifications in adalimumab, mainly in Met, His, Trp, and Tyr, were not found to be sufficient in absence of particle formation to induce increased CD4+ T cell proliferation or cytokine release despite less decreased TNFα inhibitory activity of adalimumab. These observations provide further evidence that particles do indeed potentiate the immunogenic potential of adalimumab.

Update on the mesentery: structure, function, and role in disease.

Over the past 5 years, systematic investigation of the mesenteric organ has expanded and shown that the mesentery is the organ in and on which all abdominal digestive organs develop and remain connected to. In turn, this observation has clarified the anatomical foundation of the abdomen and the fundamental order at that level. Findings related to the shape and development of the mesentery have illuminated its function, advancing our understanding of the pathobiology, diagnosis, and treatment of several abdominal and systemic diseases. Inclusion of the mesentery in surgical resections alters the course of benign and malignant diseases. Mesenteric-based scoring systems can enhance the radiological interpretation of abdominal disease. Emerging findings reconcile observations across scientific and clinical fields and have been assimilated into reference curricula and practice guidelines. This Review summarises the developmental, anatomical, and clinical advances made since the mesentery was redesignated as an organ in 2016.

Discovery and characterization of the Crustacean hyperglycemic hormone precursor related peptides (CPRP) and orcokinin neuropeptides in the sinus glands of the blue crab Callinectes sapidus using multiple tandem mass spectrometry techniques.

The crustacean sinus gland (SG) is a well-defined neuroendocrine site that produces numerous hemolymph-borne agents including the most complex class of endocrine signaling molecules-neuropeptides. Via a multifaceted mass spectrometry (MS) approach, 70 neuropeptides were identified including orcokinins, orcomyotropin, crustacean hyperglycemic hormone (CHH) precursor-related peptides (CPRPs), red pigment concentrating hormone (RPCH), pigment dispersing hormone (PDH), proctolin, RFamides, RYamides, and HL/IGSL/IYRamide. Among them, 15 novel orcokinins, 9 novel CPRPs, 1 novel orcomyotropin, 1 novel Ork/Orcomyotropin-related peptide, and 1 novel PDH were de novo sequenced via collision induced dissociation (CID) from the SG of a model organism Callinectes sapidus. Electron transfer dissociation (ETD) was used for sequencing of intact CPRPs due to their large size and higher charge state. Capillary isoelectric focusing (CIEF) was employed for separation of members of the orcokinin family, which is one of the most abundant neuropeptide families observed in the SG. Collectively, our study represents the most complete characterization of neuropeptides in the SG and provides a foundation for future investigation of the physiological function of neuropeptides in the SG of C. sapidus.

Emergent General Surgery Operations in Patients With Left Ventricular Assist Devices.

BACKGROUND: The left ventricle assist device (LVAD) patient population is rapidly expanding. Unique characteristics of these patients complicate the management of noncardiac surgical problems. Emergent general surgery (EGS) intervention is often warranted but remains poorly described. We reviewed EGS consultations in LVAD patients to better understand these patients. METHODS: During a 12-year period, 301 LVAD patients were reviewed. Demographics, comorbidities, reason for EGS consultation, operative intervention, transplantation, and mortality were analyzed. Wilcoxon, Fisher's exact, and chi-square tests were used for analysis. Statistical significance was P < .05. RESULTS: A total of 139 (46.2%) patients required EGS consultation. EGS consultations were older (63 vs 57 years; P = .002), primarily Caucasian (86%), and male (83%) with average preimplant cardiac index of 1.84. Comorbidities were similar between those with and without EGS consultation. Gastrointestinal (GI) bleeding was the most common reason for consultation (53%), followed by abdominal pain (22%) and bowel ischemia/obstruction (19%). Of EGS consultations, 77% were on warfarin and 60% on aspirin. Procedures were not withheld: 46% required esophagogastroduodenoscopy (EGD) and 30% required colonoscopy. Surgical intervention was performed in 28% of EGS consults-49% emergent (within 24 hours) and 44% urgent (during hospitalization). Mean time to surgery was 48 days after LVAD placement. EGS intervention precluded 7 (18%) patients from heart transplantation and 10 (26%) patients suffered perioperative mortality. Elevated lactic acid was associated with increased mortality. CONCLUSION: EGS consultation is necessary in almost half of all LVAD patients, most commonly for GI bleed. EGD/colonoscopy can be safely used to manage the majority of these consultations; one-third will require surgery. High lactic acid is associated with higher mortality. Additional analysis of this population is required for improving surgical management.

Asymptomatic Cholelithiasis and Bariatric Surgery: a Comprehensive Long-Term Analysis of the Risks of Biliary Disease in Patients Undergoing Primary Roux-en-Y Gastric Bypass.

PURPOSE: Currently, there is little consensus on management of the in situ gallbladder of patients undergoing gastric bypass. Our aim was to evaluate outcomes of selective concomitant cholecystectomy (CCY) and long-term biliary outcomes after Roux-en-Y gastric bypass (RYGB). MATERIALS AND METHODS: We performed a retrospective analysis of patients undergoing laparoscopic RYGB (LRYGB) between 2008 and 2018. Chi-square, Fisher's exact, or Wilcoxon rank-sum tests were used to compare outcomes. Concomitant CCY was performed on a selective basis. RESULTS: Three thousand and four patients underwent a RYGB (LRYGB n = 2458, open RYGB n = 546). Fifty-two percent (n = 1670) of patients had undergone CCY at any stage. Thirty-one percent of patients (n = 933) had CCY prior to RYGB, 13% (n = 403) had a concomitant CCY and 13% (n = 214) of the remainder required interval CCY. In the LRYGB subgroup, 29.9% (n = 735) had a prior CCY; 12.9% (n = 202) of those with an in situ gallbladder required interval CCY. Those who underwent concomitant CCY/LRYGB (n = 328) were compared with LRYGB alone (n = 1231). The concomitant CCY group was significantly older and had higher percentage of females, higher preoperative BMI, higher Charlson Comorbidity Index, and a higher medication count. There was no significant difference in BMI nadir, length of stay, complications, or mortality. Interval CCY had a higher incidence of CCY-related complications. CONCLUSION: Our study suggests a higher percentage of bariatric patients with in situ gallbladders will undergo interval CCY than documented in recently published guidelines. Concomitant CCY can be performed without an increase in length of stay or complications. Interval CCY may be associated with a higher complication rate.

Role of sialic acid binding specificity of the 1918 influenza virus hemagglutinin protein in virulence and pathogenesis for mice.

The 1918 influenza pandemic caused more than 40 million deaths and likely resulted from the introduction and adaptation of a novel avian-like virus. Influenza A virus hemagglutinins are important in host switching and virulence. Avian-adapted influenza virus hemagglutinins bind sialic acid receptors linked via alpha2-3 glycosidic bonds, while human-adapted hemagglutinins bind alpha2-6 receptors. Sequence analysis of 1918 isolates showed hemagglutinin genes with alpha2-6 or mixed alpha2-6/alpha2-3 binding. To characterize the role of the sialic acid binding specificity of the 1918 hemagglutinin, we evaluated in mice chimeric influenza viruses expressing wild-type and mutant hemagglutinin genes from avian and 1918 strains with differing receptor specificities. Viruses expressing 1918 hemagglutinin possessing either alpha2-6, alpha2-3, or alpha2-3/alpha2-6 sialic acid specificity were fatal to mice, with similar pathology and cellular tropism. Changing alpha2-3 to alpha2-6 binding specificity did not increase the lethality of an avian-adapted hemagglutinin. Thus, the 1918 hemagglutinin contains murine virulence determinants independent of receptor binding specificity.

Comparison of short-term outcomes following Roux-en-Y gastric bypass in male and female patients using the MBSAQIP database.

BACKGROUND: Male sex has long been identified as a risk factor for adverse outcomes, including mortality, after Roux-en-Y gastric bypass (RYGB). OBJECTIVES: The objective of this study was to compare short-term outcomes of patients undergoing laparoscopic RYGB based on biologic sex. SETTING: Geisinger Medical Center, Danville, PA. METHODS: Patients undergoing RYGB in the 2015, 2016, and 2017 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database were propensity matched 1:1 to compare 30-day outcomes between male and female sex. RESULTS: A total 47,906 patients were included (23,953 men/23,953 women). The overall complication rate was higher in female patients (11.5% versus 10.2%; P < .001) with no difference in mortality related to RYGB at 30 days. No significant differences were seen between sexes for organ space surgical site infection or septic shock. Women had significantly more superficial surgical site infections (P = .002), urinary tract infections (P < .001), readmissions (P < .001), and reinterventions (P < .001). Men had significantly more episodes of unplanned intubation (P = .008), extended ventilator use (P = .01), progressive renal insufficiency (P = .01), acute renal failure (P = .008), cardiac arrest (P = .005), intensive care unit admission (P < .001), all-cause 30-day mortality (P = .038), and inpatient mortality rate (P < .001). CONCLUSIONS: Male sex has been identified as a risk factor for adverse events and mortality after RYGB in several risk models. This study demonstrates an overall increased risk of both all-cause mortality and inpatient mortality. The study, however, did not demonstrate a difference in bariatric-related mortality. The prevalence of both major and minor complications was mixed between sexes, while women had a higher overall complication rate after RYGB. The abundance of data available within the MBSAQIP Participant Use Data File facilitates the creation of tools like risk models for bariatric surgery, such as the MBSAQIP Risk calculator.

Loop system for creating jet fuel vapor standards used in the calibration of infrared spectrophotometers and gas chromatographs.

A whole body inhalation study of mixed jet fuel vapor and its aerosol necessitated the development of a method for preparing vapor only standards from the neat fuel. Jet fuel is a complex mixture of components which partitions between aerosol and vapor when aspirated based on relative volatility of the individual compounds. A method was desired which could separate the vapor portion from the aerosol component to prepare standards for the calibration of infrared spectrophotometers and a head space gas chromatography system. A re-circulating loop system was developed which provided vapor only standards whose composition matched those seen in an exposure system. Comparisons of nominal concentrations in the exposure system to those determined by infrared spectrophotometry were in 92-95% agreement. Comparison of jet fuel vapor concentrations determined by infrared spectrophotometry compared to head space gas chromatography yielded a 93% overall agreement in trial runs. These levels of agreement show the loop system to be a viable method for creating jet fuel vapor standards for calibrating instruments.

Elevated hydrostatic pressure promotes protein recovery from formalin-fixed, paraffin-embedded tissue surrogates.

High-throughput proteomic studies on formalin-fixed, paraffin-embedded (FFPE) tissues have been hampered by inefficient methods to extract proteins from archival tissue and by an incomplete knowledge of formaldehyde-induced modifications to proteins. We previously reported a method for the formation of 'tissue surrogates' as a model to study formalin fixation, histochemical processing, and protein retrieval from FFPE tissues. In this study, we demonstrate the use of high hydrostatic pressure as a method for efficient protein recovery from FFPE tissue surrogates. Reversal of formaldehyde-induced protein adducts and crosslinks was observed when lysozyme tissue surrogates were extracted at 45 000 psi and 80-100 degrees C in Tris buffers containing 2% sodium dodecyl sulfate and 0.2 M glycine at pH 4. These conditions also produced peptides resulting from acid-catalyzed aspartic acid cleavage. Additives such as trimethylamine N-oxide or copper (II) chloride decreased the total percentage of these aspartic acid cleavage products, while maintaining efficient reversal of intermolecular crosslinks in the FFPE tissue surrogates. Mass spectrometry analysis of the recovered lysozyme yielded 70% sequence coverage, correctly identified all formaldehyde-reactive amino acids, and demonstrated hydrolysis at all of the expected trypsin cleavage sites. This study demonstrates that elevated hydrostatic pressure treatment is a promising approach for improving the recovery of proteins from FFPE tissues for proteomic analysis.

Label-free quantitative comparison of cerebrospinal fluid glycoproteins and endogenous peptides in subjects with Alzheimer's disease, mild cognitive impairment, and healthy individuals.

PURPOSE: The goal of this study is to investigate putative molecular dynamic changes in cerebrospinal fluids (CSFs) collected from individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD) as compared to healthy controls. EXPERIMENTAL DESIGN: The CSF samples from 12 subjects comprised of four cognitively normal individuals and eight patients with MCI and AD, respectively. Two aliquots of each CSF samples (total 1 mL) of each participant are used for this study. Endogenous peptide separations are performed using 10 000 molecular weight cut-off filters followed by LC-MS/MS identification and quantitation while lectin-enrichment chromatography is used to enrich glycoproteins in CSF followed by trypsin digestion and subsequent LC-MS/MS for shotgun identification and label-free quantitation. RESULTS: Using an optimized submicrogram peptide separation with molecular weight cut-off filtration and an in house-constructed database, 645 peptides are identified. Glycoproteins are enriched by lectin affinity chromatography, resulting in 795 identified proteins. The discovery and alterations of proSAAS-derived peptides and transthyretin are described and their roles in AD are discussed. CONCLUSIONS AND CLINICAL RELEVANCE: Comprehensive identification of endogenous CSF peptidome is achieved. Fifteen proteins are found to be differentially expressed among the three groups. The dynamic changes of transthyretin are reported for the first time.

Outcome differences between young children and adolescents undergoing kidney transplantation.

BACKGROUND/PURPOSE: Although graft loss remains the biggest challenge for all pediatric kidney transplant (KT) recipients, unique challenges exist within different age groups. We aim to evaluate the different characteristics and graft survival outcomes of young children and adolescents undergoing KT. METHODS: Children who underwent isolated KT between 2000 and 2013 at our institution were included in this retrospective analysis. Patient characteristics and outcomes were compared using student's t-test, chi-square test, Kaplan-Meier curve and Cox proportional hazards model. RESULTS: Of 73 children who underwent KT, 31 were <12 (young children), and 42 were ≥ 12 years old (adolescents). Overall patient survival was 100%. The younger group had superior 5-year (100% vs. 75.5%) and 10-year (94.4% vs. 43.8%) graft survival (p=0.008). Factors predictive of poor graft survival on multivariate analysis were older age at transplantation (HR 1.2, CI 1-1.4, p=0.047), female gender (HR 9.0, CI 1.9-43, p=0.006), and acute rejection episodes (HR 13, CI 2-90, p=0.008). The most common causes of graft loss were acute and chronic rejection episodes and immunosuppression nonadherence. CONCLUSION: Adolescents undergoing KT have inferior graft survival compared to younger children. In adjusted modeling, children with older age, female gender, and acute rejection episodes have inferior graft survival.

Professionalism reconsidered: physician payment in a small-practice environment.

Traditional fee-for-service health insurance rested on the assumption that doctors have primary responsibility for decisions about care. Managed competition assumed a new model based on corporate medicine, which has not materialized; also, consumers' ability to replace doctors as primary medical decisionmakers is unproven. Data on practice size show that doctors and patients continue to prefer the small-practice setting, where the doctor's role as the patient's agent is salient. The persistence of the small practice suggests that medical professionalism remains the cornerstone of the health system. If so, it may be more appropriate to pursue quality-oriented refinements of traditional payment approaches, rather than radical transformation.

Joint custody: bipartisan interest expands scope of tax-credit proposals.

The Bush administration's proposal to use tax credits to cover the uninsured has not attracted enough bipartisan support to make headway in a divided Congress. Democratic objections have centered on the administration's insistence that the credits be used primarily in the individual market. But bipartisan exploration of alternative credit designs has continued on Capitol Hill. Democratic proposals to include health coverage for laid-off workers in debate over the post-September 11 economic stimulus package and more recently in the Trade Adjustment Assistance Act have resulted in increased awareness that tax credits might be used for employer groups as well as in the nongroup market.